1. Field of Disclosure
This disclosure generally relates to a cleaning device used in a facsimile machine, a printer, a copier, a multifunction printer or other similar machine, a process cartridge including the cleaning device and an image forming apparatus including the process cartridge.
2. Discussion of the Background Art
An image forming apparatus of an electrophotography type locates a charging device, an optical scanning device, a developing device, a transfer device, a charge removing device, and a cleaning device around a photoconductive drum. The charging device takes a uniformly charge on a surface of the photoconductive drum by a corona discharge. The optical scanning device writes a latent electrostatic image on the surface of the photoconductive drum, and the developing device develops a toner image. After that, an intermediate transfer belt transfers a toner on the photoconductive drum thereon to contact with the toner image on the photoconductive drum and to apply a bias. In addition, a secondary transfer roller transfers the toner on the intermediate transfer belt to a sheet. A fixing device fixes the toner on the sheet with heat to apply the transferred the toner to the sheet. After the transferring, the charge removing device removes a charge and the cleaning device cleans the surface of the photoconductive drum.
After that, the image forming apparatus repeats a next process in accordance with the above.
A conventional cleaning device for an image forming apparatus is shown in FIG. 12.
FIG. 12 shows the cleaning device using a cleaning blade 900. The cleaning device cleans almost all the toner that makes contact with a photoconductive drum 901. Japanese Examined Patent Application Publication No. 2011-053613 and Japanese Examined Patent Application Publication No. 2005-181570 disclose cleaning devices in accordance with FIG. 12.
FIG. 13 shows a cleaning device using cleaning brushes 908 and 906. The charging devices 907 apply a bias to the cleaning brushes 908 and 906 and collection rollers 912. The cleaning brushes 908 and 906 electrically clean toner 903 on the photoconductive drum 901. The collection rollers 912 electrically collect the toner 903 on the cleaning brushes 908 and 906. Collection blades 914 collect the toner 903 on the collection rollers 912. The cleaning brushes 908 and 906 collect more toner than the cleaning blade 900.
Japanese Examined Patent Application Publication No. 2010-170020 and Japanese Examined Patent Application Publication No. 2010-181669 disclose cleaning devices in accordance with FIG. 13.
FIG. 14 shows a cleaning device using the cleaning brush 906 and the cleaning blade 900. The cleaning blade 900 locates a downstream side in a rotation direction of the photoconductive drum 901 with respect to the cleaning brush 906. The cleaning brush 906 removes almost all of the toner 903 and the cleaning blade 900 removes remaining toner. Japanese Patent No. 4597837 discloses a cleaning device in accordance with FIG. 14.
The collection blades 914, discussed above, are made of a thin metal.
As shown in FIG. 15, a collection blade 914′, which includes a thin blade 916 welded to a thick blade holder 915, clamps a frame of a cleaning apparatus as shown in FIG. 15.
Japanese Examined Patent Application Publication No. 2011-053613 discloses a collection blade that forms a rectangular shape and is detachable from a blade holder and a metal blade by a screw.
FIG. 16 illustrates a conventional cleaning blade experiencing entrainment.